A slow-moving low-pressure system has been dumping rain over western Europe since early this week, according to AccuWeather. Parts of Germany saw more rain in a day than they would typically see in the entire month. The same system led to floods in London on Monday; it is now heading to southern Europe. Scientists see two ways in which climate change likely contributed to flooding: the amount of rain delivered and the slow pace of the storm Warmer air can hold more water. That’s because at higher temperatures, water molecules condense into vapor and concentrate in the atmosphere. It’s the same physics behind clothes dryers and dishwashers; it’s also why cold drinks sweat. For every 1.8 degrees Fahrenheit of warming, scientists estimate that the atmosphere can hold about 7 percent more moisture.
With more moisture in the atmosphere, formations like the low-pressure system over Europe or hurricanes in the Atlantic will produce more rainfall. Whether floods result from heavy rainfall depends on a number of factors, including previous rainfall, urban development, and geography, such as whether a region is in a valley. But, the slow movement of weather systems carrying large amounts of precipitation will make these rain events worse in Europe The Arctic and Antarctica are warming at a rate two to three times faster than the rest of the planet. Scientists think this warming is destabilizing the jet stream, the counter clockwise current of air circling the Northern Hemisphere. When the temperature difference between the poles and the equator is high, the jet stream blows stronger and more evenly, but when the poles warm, that temperature difference is less, which slows down the jet stream. We would expect weather changes every three to seven days, but now we have weather patterns that last for weeks scientists are currently studying how much of this particular catastrophe can be attributed to climate change. The World Weather Attribution Initiative, which studies the connection between extreme weather and climate change, will study how more intense the floods occur as a result of human influence. Earlier this month, an international team of scientists from the initiative determined that the Pacific Northwest’s extreme heat wave would have been “virtually impossible” without climate change.
The rainfall set new records over the Rhine River Basin in Germany, where most of the flooding occurred. Streets became navigable only by boat, homes were inundated, sinkholes opened up, and part of a castle was swept away. While scientists are still piecing together how climate change might have influenced this one weather event, they say it shows key characteristics of how storms will be impacted by climate change: higher amounts of rainfall falling for longer. Germany and Belgium, as well as parts of the Netherlands and Luxembourg, are grappling with devastating floods from intense rainfall over the past several days. More than 125 were confirmed dead as of Friday. As rescue teams moved in to help affected citizens, European leaders used the floods to reinforce their message that action needs to be taken to curb and adapt to climate change. This event shows that even rich countries like Germany are not safe from very severe climate impacts,